This work presents an online approximation method for the multichannel Wiener filter (MWF) noise reduction technique with preservation of the noise interaural level difference (ILD) for binaural hearing-aids. The steepest descent method is applied to a previously proposed MWF-ILD cost function to both approximate the optimal linear estimator of the desired speech and keep the subjective perception of the original acoustic scenario. The computational cost of the resulting algorithm is estimated in terms of multiply and accumulate operations, whose number can be controlled by setting the number of iterations at each time frame...

This longitudinal study aimed to identify auditory plasticity promoted by a cochlear implant in children with asymmetric hearing loss. Participants included 10 children who experienced (mean ± SD) 3.1 ± 3.6 years of asymmetric hearing (difference of 47.2 ± 47.6 dB) before receiving an implant at age 8.7 ± 5.1 years. Multi-channel electroencephalography was measured at initial implant use (5.8 ± 3.2 days) and after 10.2 ± 4.1 months in each child. Monaurally presented stimuli consisted of 36 ms trains of 9 acoustic clicks/biphasic electric pulses at a rate of 250 Hz, repeated at 1 Hz...

Accurate localization of complex sounds involves combining interaural information across frequencies to produce a single location percept. Interaural level differences (ILDs) are highly frequency dependent and it is unclear how the auditory system combines differing ILDs across frequency. Therefore, ILD just noticeable differences (JNDs) and intracranial lateralization were measured in young normal-hearing listeners using single- and multi-band stimuli. The bands were 300-ms, 10-Hz narrowband noises; the multi-band condition had three bands; they started and ended synchronously; they were located around three different frequency regions (750, 2000, or 4000 Hz); they had five different frequency separations that ranged from unresolved to resolved; the bands were dichotic with the same non-zero ILD (targets) or were diotic with zero ILD (interferers)...

Hearing loss is the most common symptom of vestibular schwannomas (VSs). The management of these lesions includes observation, radiosurgery, and microsurgical resection. Hearing preservation and rehabilitation are the major challenges after the tumor treatment. A 43-year-old man with previous left-sided profound hearing loss and tinnitus presented with a 2-mm left-sided intracanalicular VS. The decision was made to perform a simultaneous cochlear implantation (CI) and microsurgical resection of the tumor. The patient did well postoperatively, with significant improvement of tinnitus, sound localization, and speech recognition in noise...

Cochlear implantation (CI) for early-onset single-sided deafness (SSD) provides a unique insight into the development and cortical reorganization of binaural pathways. This case series aimed to investigate the impact of duration of deafness on CI outcomes as measured by cortical evoked auditory potentials (CAEPs). Four adults with early-onset SSD were studied after CI. The adults had a duration of deafness of 22, 24, 42, and 38 years before implantation. CAEPs and speech perception in noise were used to investigate binaural cortical pathways and function...

Little is known about the perception of artificial spatial hearing by hearing-impaired subjects. The purpose of this study was to investigate how listeners with hearing disorders perceived the effect of a spatialization feature designed for wireless microphone systems. Forty listeners took part in the experiments. They were arranged in four groups: normal-hearing, moderate, severe, and profound hearing loss. Their performance in terms of speech understanding and speaker localization was assessed with diotic and binaural stimuli...

OBJECTIVE: We investigated whether speech intelligibility and listening effort for hearing-aid users is affected by semantic context and hearing-aid setting. DESIGN: Participants heard target sentences spoken in a reverberant background of cafeteria noise and competing speech. Participants reported each sentence verbally. Eight participants also rated listening effort after each sentence. Sentence topic was either the same as, or different from, the previous target sentence...

Purpose: The purpose of this study was to determine whether a significant order effect exists in the binaural bithermal caloric test. Method: Fifteen volunteers (mean age = 24.3 years, range = 18-38 years) with no history of vestibular disorder, hearing loss, concussion, or neurological disease underwent caloric testing on 3 occasions. Irrigations were randomized using 8 possible order combinations. The parameters of interest included unilateral weakness, directional preponderance, total response from the right ear, and total response from the left ear...

A model using temporal-envelope cues was previously developed to explain perceptual interference effects between amplitude and frequency modulation (FM). Since that model could not accurately predict FM sensitivity and the interference effects, temporal fine-structure (TFS) cues were added to the model. Thus, following the initial stage of the model consisting of a linear filterbank simulating cochlear filtering, processing was split into an 'envelope-path' based on envelope power cues, and a 'TFS-path' based on a measure of the distribution of time-intervals between successive zero-crossings...

Interactions between sensory pathways such as the visual and auditory systems are known to occur in the brain, but where they first occur is uncertain. Here, we show a multimodal interaction evident at the eardrum. Ear canal microphone measurements in humans (n = 19 ears in 16 subjects) and monkeys (n = 5 ears in three subjects) performing a saccadic eye movement task to visual targets indicated that the eardrum moves in conjunction with the eye movement. The eardrum motion was oscillatory and began as early as 10 ms before saccade onset in humans or with saccade onset in monkeys...

Several behavioural studies in humans have shown that listening to sounds with two ears, i.e., binaural hearing, provides the human auditory system with extra information on the sound source that is not available when sounds are only perceived through one ear, i.e., monaurally. Binaural processing involves the analysis of phase and level differences between the two ear signals. Since monaural cochlea processing (in each ear) precedes the neural stages responsible for binaural processing properties it is reasonable to assume that properties of the cochlea may also be observed in binaural processing...

In studies investigating binaural processing in human listeners, relatively long and task-dependent time constants of a binaural window ranging from 10 ms to 250 ms have been observed. Such time constants are often thought to reflect "binaural sluggishness." In this study, the effect of binaural sluggishness on binaural unmasking of speech in stationary speech-shaped noise is investigated in 10 listeners with normal hearing. In order to design a masking signal with temporally varying binaural cues, the interaural phase difference of the noise was modulated sinusoidally with frequencies ranging from 0...

OBJECTIVE: The binaural-hearing system interaurally compares inputs, which underlies the ability to localize sound sources and to better understand speech in complex acoustic environments. Cochlear implants (CIs) are provided in both ears to increase binaural-hearing benefits; however, bilateral CI users continue to struggle with understanding speech in the presence of interfering sounds and do not achieve the same level of spatial release from masking (SRM) as normal-hearing listeners...

BACKGROUND AND OBJECTIVES: The ability to localize a sound source is one of the binaural hearing benefits in a horizontal plane based on interaural time difference and interaural intensity difference. Unilateral or bilateral asymmetric hearing loss will affect binaural hearing and lead to sound locating errors. In this cross sectional analytical descriptive study, the localization error was investigated when participants turned their heads to the sound source with closed eyes and after simulating unilateral hearing loss by placing earplugs inside the right ear canal...

OBJECTIVE: Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading span. DESIGN: Using a computer simulation of bilaterally fitted HAs, four settings were tested: (1) unprocessed, (2) directional microphones, (3) single-channel noise reduction, and (4) binaural coherence-based noise reduction...

Both harmonic and binaural signal properties are relevant for auditory processing. To investigate how these cues combine in the auditory system, detection thresholds for an 800-Hz tone masked by a diotic (i.e., identical between the ears) harmonic complex tone were measured in six normal-hearing subjects. The target tone was presented either diotically or with an interaural phase difference (IPD) of 180° and in either harmonic or "mistuned" relationship to the diotic masker. Three different maskers were used, a resolved and an unresolved complex tone (fundamental frequency: 160 and 40 Hz) with four components below and above the target frequency and a broadband unresolved complex tone with 12 additional components...

Using a well-established binaural-listening paradigm the ability to intentionally switch auditory selective attention was examined under anechoic, low reverberation (0.8 s) and high reverberation (1.75 s) conditions. Twenty-three young, normal-hearing subjects were tested in a within-subject design to analyze influences of the reverberation times. Spoken word pairs by two speakers were presented simultaneously to subjects from two of eight azimuth positions. The stimuli consisted of a single number word, (i...

OBJECTIVES: To explore the pathogenic causes of a proband who was diagnosed with non-syndromic hearing loss. METHODS: We performed targeted capture of 159 known deafness-related genes and next-generation sequencing in the proband who was tested negative for the twenty hotspot variants in four common deafness-related genes(GJB2, GJB3, SLC26A4 and MTRNR1); Clinical reassessments, including detailed audiological and ocular examinations were performed in the proband and his normal parents...

OBJECTIVES: Among the many advantages of binaural hearing are the abilities to localize sounds in space and to attend to one sound in the presence of many sounds. Binaural hearing provides benefits for all listeners, but it may be especially critical for military personnel who must maintain situational awareness in complex tactical environments with multiple speech and noise sources. There is concern that Military Service Members who have been exposed to one or more high-intensity blasts during their tour of duty may have difficulty with binaural and spatial ability due to degradation in auditory and cognitive processes...